<span>Answer:
Chemical equations are balanced in order to: 1) satisfy the Law of Conservation of Mass, and 2) establish the mole relationships needed for stoichiometric calculations. The Law of Conservation of Mass: The Law of Conservation of Mass states that mass cannot be created or destroyed.</span>
Answer:
3.49 g
Explanation:
The mass is the product of volume and density:
(8.96 g/cm³)(0.39 cm³) ≈ 3.49 g
The mass of a pure-copper penny would be 3.49 g.
Answer:
9.35g
Explanation:
The molarity equation establishes that:

So, we have information about molarity (2M) and volume (80 ml=0.08 l), with that, we can find the moles of solute:


The mathematical equation that establishes the relationship between molar weight, mass and moles is:


We have MW (58.44g/mole) and n (0.16 mol), and we need to find m (grams of salt needed) to solve the problem:
